/*
 * Small jpeg decoder library (Internal header)
 *
 * Copyright (c) 2006, Luc Saillard <luc@saillard.org>
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *  this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright notice,
 *  this list of conditions and the following disclaimer in the documentation
 *  and/or other materials provided with the distribution.
 *
 * - Neither the name of the author nor the names of its contributors may be
 *  used to endorse or promote products derived from this software without
 *  specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */


#ifndef __TINYJPEG_INTERNAL_H_
#define __TINYJPEG_INTERNAL_H_

/* #include <setjmp.h> */

#define SANITY_CHECK 0
#define TJ_DEBUG 0

#define uint8_t  unsigned char
#define uint16_t unsigned short
#define uint32_t unsigned int
#define int16_t  short

#define _JBLEN  256

#define HUFFMAN_BITS_SIZE  256
#define HUFFMAN_HASH_NBITS 9
#define HUFFMAN_HASH_SIZE  (1UL << HUFFMAN_HASH_NBITS)
#define HUFFMAN_HASH_MASK  (HUFFMAN_HASH_SIZE - 1)

#define HUFFMAN_TABLES	   4
#define COMPONENTS	   3
#define JPEG_MAX_WIDTH	   2048
#define JPEG_MAX_HEIGHT	   2048

struct jdec_private;

struct huffman_table {
    /* Fast look up table, using HUFFMAN_HASH_NBITS bits we can have directly the symbol,
    * if the symbol is <0, then we need to look into the tree table */
    short int lookup[HUFFMAN_HASH_SIZE];
    /* code size: give the number of bits of a symbol is encoded */
    unsigned char code_size[HUFFMAN_HASH_SIZE];
    /* some place to store value that is not encoded in the lookup table
    * FIXME: Calculate if 256 value is enough to store all values
    */
    uint16_t slowtable[16-HUFFMAN_HASH_NBITS][256];
};

struct component {
    unsigned int Hfactor;
    unsigned int Vfactor;
    float *Q_table;		/* Pointer to the quantisation table to use */
    struct huffman_table *AC_table;
    struct huffman_table *DC_table;
    short int previous_DC;	/* Previous DC coefficient */
    short int DCT[64];		/* DCT coef */
#if SANITY_CHECK
    unsigned int cid;
#endif
};

typedef struct _jmp_buf {
    int _jb[_JBLEN + 1];
} jmp_buf[1];

typedef void (*decode_MCU_fct) (struct jdec_private *priv);
typedef void (*convert_colorspace_fct) (struct jdec_private *priv);

struct jdec_private {
    /* Public variables */
    uint8_t *components[COMPONENTS];
    unsigned int width, height;	/* Size of the image */
    unsigned int flags;

    /* Private variables */
    const unsigned char *stream_begin, *stream_end;
    unsigned int stream_length;

    const unsigned char *stream;	/* Pointer to the current stream */
    unsigned int reservoir, nbits_in_reservoir;

    struct component component_infos[COMPONENTS];
    float Q_tables[COMPONENTS][64];		/* quantization tables */
    struct huffman_table HTDC[HUFFMAN_TABLES];	/* DC huffman tables   */
    struct huffman_table HTAC[HUFFMAN_TABLES];	/* AC huffman tables   */
    int default_huffman_table_initialized;
    int restart_interval;
    int restarts_to_go;				/* MCUs left in this restart interval */
    int last_rst_marker_seen;			/* Rst marker is incremented each time */

    /* Temp space used after the IDCT to store each components */
    uint8_t Y[64*4], Cr[64], Cb[64];

    jmp_buf jump_state;
    /* Internal Pointer use for colorspace conversion, do not modify it !!! */
    uint8_t *plane[COMPONENTS];
};

#if defined(__GNUC__) && (__GNUC__ > 3) && defined(__OPTIMIZE__)
#define __likely(x)       __builtin_expect(!!(x), 1)
#define __unlikely(x)     __builtin_expect(!!(x), 0)
#else
#define __likely(x)       (x)
#define __unlikely(x)     (x)
#endif

#define IDCT tinyjpeg_idct_float
void tinyjpeg_idct_float (struct component *compptr, uint8_t *output_buf, int stride);

int setjmp(jmp_buf env);
void longjmp(jmp_buf env, int val);

#endif
